Our Corner Of The Milky Way Galaxy Is Much Bigger Than Previously Thought

New study reveals that Local Arm where our solar system lies is about four times larger than scientists thought

Scientists have been studying galaxy Milky Way and solar system for decades but they still keep coming up with unusual discoveries. Now, a new research reveals that our corner of Milky Way is much bigger than previously estimated.

The Milky Way is a barred spiral galaxy, about 100,000 light-years across. If we could look down on it from the top, we will see a central bulge with large spiral arms of stars, dust and gas stretching out of it. Scientists have long been confused about the number of galactic arms our galaxy has got but newer surveys largely led to the picture of four major arms as well as several small arms and spurs. Our solar system is located at the edge of what's called the Local Arm and it lies between two major arms, Perseus and Sagittarius.

For the longest time, the Local Arm, also known as Orion Arm, was thought to be a tiny thing but a new research suggests that it is actually much bigger than previously thought. Researchers estimate that Local Arm stretches more than 20,000 light-years long, about four times what scientists had thought before. Despite that, it is still considerably shorter than the Milky Way’s four main arms.

“When we actually measured distances in the Local Arm we were surprised. A lot of the material that we thought was in a nearby arm was actually in the Local Arm.” Mark Reid of the Harvard-Smithsonian Center for Astrophysics told National Geographic.

To arrive at this conclusion, researchers analyzed the radio waves collected by Very Long Baseline Array, a system comprising of 10 radio telescopes which is operated remotely from a base in New Mexico.

In 2010, the VLBA was assigned to a long-term program to determine the complete 3D structure of Milky Way. Upon the completion, the program is expected to measure the fundamental galactic parameters with 1% accuracy, which will eventually help researchers to quantify the distribution of normal and dark matter in our galaxy.

"Since we are inside of it we can’t really see what it looks like," said Reid. "It's sort of like 500 years ago, when people wanted to know what the rest of the Earth looked like. So our project hopes to help us better understand the nature of the Milky Way by measuring distances between regions.”

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Hira BashirThe latest discoveries in science are the passion of Hira Bashir (Google+). With years of experience, she is able to spot the most interesting new achievements of scientists around the world and cover them in easy to understand reporting.